<TABLE> <S> <C>

<PAGE>
<ARTICLE> 5
<LEGEND>
This schedule contains summary financial information extracted from
the consolidated condensed balance sheets and the consolidated condensed
statements of operations for the periods ended March 31, 1997, June 30,
1997 and September 30, 1997.
</LEGEND>
<RESTATED>
<MULTIPLIER> 1,000

<S>                             <C>                     <C>                     <C>
<PERIOD-TYPE>                   3-MOS                   6-MOS                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1997             DEC-31-1997             DEC-31-1997
<PERIOD-START>                             JAN-01-1997             JAN-01-1997             JAN-01-1997
<PERIOD-END>                               MAR-31-1997             JUN-30-1997             SEP-30-1997
<CASH>                                          28,941                  33,440                  50,520
<SECURITIES>                                    12,064                   5,690                   3,855
<RECEIVABLES>                                   14,414                  12,683                  10,849
<ALLOWANCES>                                     1,559                     579                     520
<INVENTORY>                                     12,682                   3,497                   3,818
<CURRENT-ASSETS>                                71,124                  59,020                  72,947
<PP&E>                                          16,603                  16,758                  14,623
<DEPRECIATION>                                   7,550                   8,681                   8,159
<TOTAL-ASSETS>                                  81,178                  68,112                  80,429
<CURRENT-LIABILITIES>                           19,188                   8,475                  20,158
<BONDS>                                              0                       0                       0
<PREFERRED-MANDATORY>                                0                       0                       0
<PREFERRED>                                          0                       0                       0
<COMMON>                                        54,116                  53,318                  53,584
<OTHER-SE>                                       7,874                   6,319                   6,687
<TOTAL-LIABILITY-AND-EQUITY>                    81,178                  68,112                  80,429
<SALES>                                         16,854                  34,581                  54,250
<TOTAL-REVENUES>                                17,092                  35,148                  55,163
<CGS>                                           16,533                  31,407                  46,837
<TOTAL-COSTS>                                   21,020                  40,910                  61,090
<OTHER-EXPENSES>                                     0                       0                       0
<LOSS-PROVISION>                                     0                       0                       0
<INTEREST-EXPENSE>                                   0                       0                       0
<INCOME-PRETAX>                                (3,563)                 (4,921)                 (4,491)
<INCOME-TAX>                                   (1,044)                 (1,383)                 (1,348)
<INCOME-CONTINUING>                            (2,519)                 (3,538)                 (3,143)
<DISCONTINUED>                                       0                       0                       0
<EXTRAORDINARY>                                      0                       0                       0
<CHANGES>                                            0                       0                       0
<NET-INCOME>                                   (2,519)                 (3,538)                 (3,143)
<EPS-PRIMARY>                                   (0.11)                  (0.15)                  (0.14)
<EPS-DILUTED>                                   (0.11)                  (0.15)                  (0.14)


</TABLE>